(PS6-C53) Impact of a Weight-loss Intervention on the Cognitive Functioning and Habit Strength of Overweight and Obese Individuals with Traumatic Brain Injury

Cognitive deficits are common after a traumatic brain injury (TBI) and correlate with brain injury severity (De Guise et al., 2014). Individuals with moderate to severe TBI are also at risk for comorbid health outcomes, including being overweight or obese (Dreer et al., 2018). Weight-loss interventions have demonstrated efficacy in improving cognition as well as weight outcomes (Markovic et al., 2021; Toman, Klimova, & Valis, 2018). However, cognitive deficits may also be a barrier to health behavior change (Favieri, Forte, & Casagrande, 2019), resulting in poorer weight loss (Dassen et al., 2018; Galioto et al., 2018) and greater difficulty changing health behaviors (Butryn et al., 2019). Cognitive functioning may also impact individuals’ ability to translate behavior change into long-term habits (Gardner, de Bruijn, & Lally, 2011; Verplanken & Orbell, 2003). However, the relationship among these factors has not been adequately examined among individuals with moderate to severe TBI engaged in a weight-loss program.

Our objective was to examine the impact of a weight-loss intervention on the cognitive functioning and habit strength of overweight and obese individuals with TBI. Results involve secondary analysis of a randomized controlled trial (RCT) comparing a modified Diabetes Prevention Program Group Lifestyle Behavioral (DPP-GLB) intervention to an attention control group (ACG) “brain health group” intervention for survivors of moderate to severe TBI.

A total of 57 adults at least 6-months post-injury completed the 12-month intervention. We analyzed data for the 47 individuals with complete longitudinal data for cognitive function, assessed via the Montreal Cognitive Assessment (MoCA), and habit strength, measured with the Self-Report Habit Index (SRHI). Both the MoCA and SRHI were completed prior to randomization into either GLB (n = 24) or ACG (n = 23) with post-assessments following completion of the 12-month interventions. Participants were primarily male (74.5%), White (87.2%) with 17% identifying as Hispanic. The average age was 42.35 years and about half of the sample sustained a TBI due to a motor vehicle collision (51.1%).

A repeated-measures ANOVA was run to determine whether cognitive function scores changed over time (from pre- to post- intervention) for the two groups. While not statistically significant (F(1, 45) = 3.038, p = .088), MoCA scores differed across the two time points, suggesting that cognitive function scores improved for the GLB group, from 25.38 (SD = 2.41) to 26.17 (SD = 2.94) and worsened for the ACG group, from 24.62 (SD = 4.09) to 23.91 (SD = 3.57). This same analyses was used to examine the change in SRHI over time between the groups, which was not significant (F(1, 46) = 0.135, p = .715; GLB = 5.18 to 5.60 (SD = 1.16/1.08) and ACG = 4.85 to 5.16 (SD = 1.30/1.29)).

Results suggest that although both groups perceived an increase in habits related to health behaviors broadly across the 12-month study, only individuals in the GLB group showed an improvement in cognitive function. Both groups perceived a change in habits, yet only the group which lost weight demonstrated gains in cognitive function. This is consistent with literature suggesting a reciprocal relationship between weight loss and cognitive function.